1. Field of the Invention
The present invention relates to a liquid crystal display (LCD) device, and more particularly, to an array substrate having high resolution patterns, an LCD device having the same, and a manufacturing method thereof.
2. Description of the Related Art
Recently, an interest regarding patterning technology for manufacturing a semiconductor device and a display device has increased. Patterning technology has a great influence on miniaturization, high integration, and production of a semiconductor device and a display device. That is, as the patterning technology becomes complicated, production decreases and error rate may increase. Photolithography using a photoresist resin reacting to light has been widely used as the related art patterning technology.
FIGS. 1A to 1E are cross-sectional views explaining a method for forming metal patterns using the related art photolithography. As illustrated in FIG. 1A, a metal film 20a is formed by depositing metal on a substrate 10. Subsequently, a photoresist resin is formed on the metal film 20a to form a photoresist film 90.
As illustrated in FIG. 1B, after a mask M is disposed over the photoresist film 90, UV light is illuminated thereon.
As illustrated in FIG. 1C, a hardening region 90a is formed from the photoresist film 90 onto which light that has passed through the mask M is illuminated. The substrate 10 is developed, and the photoresist film 90 except the hardening region 90a is removed. Therefore, photoresist patterns having the hardening region 90a are formed.
As illustrated in FIG. 1D, etching is performed using the photoresist patterns as a mask.
As illustrated in FIG. 1E, metal patterns 20 are formed on the substrate 10 by stripping the photoresist patterns.
Because the related art photolithography requires five processes of a depositing process, an exposure process, a developing process, an etching process, and a stripping process in order to form one metal pattern, the entire process is complicated. Also, the related art photolithography requires an exposure equipment having a light source for illuminating light. However, such exposure equipment is considerably expensive. In the case where patterns are formed using this expensive exposure equipment, process costs increase. Further, the related art photolithography forms photoresist patterns using light. However, light can be diffracted due to limit of the exposure equipment, which can make the photoresist patterns imprecise. Accordingly, metal patterns formed using such photoresist patterns can also be imprecise such that high resolution patterns cannot be obtained. Yield considerably decreases due to such imprecise patterns.